It's not immediately obvious, but the main change after Tortage is the complete lack of faction. After level 20, when you return to your homeland, you don't stand for anything in particular any more. The quest contacts approach you not as a potential hero or ally, but as a runner of errands. Yes, the player has a culture - Stygian, Cimmerian or Aquilonian - but that's not the same as having a faction. Factions cause conflict.

So what was your faction in Tortage? You were a freed slave, allied to the Resistance, and the opposing faction was Strom and his Red Hand. There's no drama without conflict, and conflict has to mean something more than just random fighting. The player has to be on some sort of a side. It doesn't matter whether you're a Hero or a Villain in CoX; what matters is that you have a side. Equally, it doesn't matter whether you're Horde or Alliance in WoW. Having a faction is what counts, not because it constrains the player, but because it makes what happens to the player meaningful in the context of the game world.